gryd,

Show a picture of the overall backflow layout. Including the two ball valves. What is the 45 degree rule? Is this a PVB or a RP BFP.

The pressure vacuum breaker (PVB) is designed to open after long periods of continuous water pressure. This type of device may be installed under a constant pressure upstream of all control valves. This device must be installed in a vertical position and at least twelve (12) inches above all downstream piping.

The reduced pressure (RP) backflow device is the highest level of protection available. This device protects from backflow and back pressure. When installing the device, a minimum of 12 inches of access and clearance between the lowest portion of the device and grade, floor or platform must be provided.

Both these types usually require annual inspection by a certified BFP plumber.

It is very unusual that ball valves especially the type you have in the pic. Sounds like your pressure is very high and the valves were closed very fast. What is you system pressure? The plumber should take the pressure reading to give a good idea of what he should do. It could happen to new ones if that is the case. JMHO Aloha

Taking labor into account and the cost of genuine Febco replacement parts, you probably should replace the whole unit. From the picture, the original installer has the device right up against the wall so you may not be able to twist it off. Therefore, you would have to cut the copper pipe at both the inlet and outlet sides, then sweat it back together. Someone was'nt thinking when they put that together. ps: water pressure has nothing to do with the ball valves cracking.

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Here is a link that might be useful: GuardianEnclousers

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